Many of the ideas you have seen regarding character device drivers are also directly applicable to block device drivers. In this chapter, therefore, I will try to concentrate on the differences between the two.
Let me say to start with that creating block device drivers under Linux seems to he a much more fiddly affair altogether, with quite a large degree of reliance placed upon macro definitions which try to hide some of the underlying complexity but which, in doing so, make your code look like it contains many magic incantations' whose purpose is not immediately apparent.